Yes, many of those people who require accessible sites will use IE 4.x. Many, however, will use pwWebSpeak (which is its own browser), or some version of Lynx (either telnetting to a Unix box, or running either the DOS or the native Win32 version), or one of a number of other browsers that don't support Javascript.
And that's just considering those who require a non-graphical interface. With alternative web access devices coming out nearly every week (PDAs, TV-based systems, digital phones, Netpliance's "i-opener" and many other alternatives to the traditional PC-based browser), the number of people using browsers that don't support Javascript will continue to grow.
The single most important error people make in talking about web accessibility is assuming that it's all about people with disabilities. It's not. It's about anyone using anything other than the two major browsers to access the web. Yes, people with disabilities are an important part of that larger group. Because their use of non-standard equipment is not a choice, but a necessity, people with disabilities need and deserve the special protections that can be provided by Section 508 of the Rehab Act and the ADA (or similar laws outside the US). But accessibility as an issue of web design, not law, applies to a much larger group. The next time you see an ad for, or an article about, some new web access device that's not PC based, the odds are pretty good that you're seeing a device that can't handle Javascript, and another group of potential customers who will be driven away if your site requires Javascript to function.
How to resolve your use of Javascript? Continue to use Javascript for form validation, just make sure that people who can't use it still are able to use your form - they just won't have their data checked on the client end. If you can't accept that, then on submission of the form, return users to a display of their data and require them to review and approve it before it is entered into the database. Server-side validation is also a perfectly reasonable option. You mentioned that Javascript error checking gives more detailed information to the user - well, not if you put in the time and effort to write your server-side code properly. It's harder on the server end, not impossible.
Adam Guasch-Melendez
EEOC
>>> Joel Sanda <joelsanda@yahoo.com> 03/24/00 04:44PM >>>
2. Since the best support for the WCAG lies in
Internet Explorer 4.x, it seems logical most people
looking for an accessible site will hit it in IE4.x.